Ruger's original Security Series hand-guns were six-shot .357 Magnum double-action revolvers in blued steel and satin stainless steel. They put Ruger on the map in terms of duty guns.
The .357 Mag. Security-Six double-action service revolver was one of the all-time great handguns. It was accurate, ergonomic, rugged, and dependable. When Bill Ruger introduced it in 1971, he wanted to offer the shooting world a top-quality double-action .357 Mag. at a low price. With an introductory retail price of $89 for the fixed-sight version and $97.50 for the adjustable-sight gun, the Security-Six was all that.
The Security-Six was offered in two basic models: one with an adjustable rear sight and one with fixed sights. The fixed-sight version came to be known as the Speed-Six. Both versions were offered in blued steel and stainless steel. The barrel was medium weight and available in 2.75-, 4.0-, and 6.0-inch lengths. Some special 3.0-inch-barreled guns were offered on a limited basis, and some revolvers were chambered for 9mm Luger. There was also a version called the Service-Six. Late in the "150-" serial number prefix range, the grip frame of the Security-Six was changed to a "highback" shape. After that, revolvers with "highback" grip frames, fixed sights, and square butts were marked "Service-Six." Prior to that change, all "lowback" revolvers were marked "Security-Six" regardless of the type of sights.
One of the innovative features of the Security-Six was that it did not have the sideplate that most other double-action revolvers had. Instead, the revolver disassembled by removing the grip screw, and then the grips, the lockwork, and the cylinder assembly could be removed.
The frame, crane, hammer, trigger, trigger guard, and other smaller parts were produced from investment castings. The barrel was a machined forging, and the cylinder was machined from bar stock. All springs were coil type.
The ejector rod housing and a raised, grooved barrel rib were integral with the barrel. And a Baughman-style quick-draw front sight was pinned to the rib.
The gun utilized a transfer bar firing mechanism, and the cylinder rotated counterclockwise when the action was operated. When the thumbpiece was pushed in, the cylinder swung out to the left. Cylinder capacity was six rounds.
I've always liked the wording Ruger used to describe the Security-Six, especially this quotation: "It [the Security-Six] is a handsome, rugged holster revolver- compact in the overall, yet massive enough to properly be designated as a heavy-duty revolver for the rigors of police and military service."
As good as the revolver was, it was not without critics. The chief complaints were that it was muzzle light and that the back of the grip frame had an uncomfortable hump that tended to make the revolver roll in the shooter's hand. Ruger addressed those concerns when the Security-Six was replaced by the GP100 in the late 1980s. Even so, the Security-Six was very popular, with approximately 1.5 million produced during the 17 years it was in production.